A turning tool as described in Patent Document 1 has been known as a cutting tool used in a cutting process of a workpiece, such as metals. The turning tool described in Patent Document 1 includes a flow path. The flow path is formed inside a tool body (holder) and branched on its way. A coolant is designed to be sprayingly supplied from two spray ports in branched flow paths toward an insert (cutting insert). The coolant is sprayed from one of the two spray ports toward a rake surface of the insert, and the coolant is sprayed from the other toward a flank surface of the insert. The turning tool in Patent Document 1 includes adjustment pieces respectively interposed in the branched flow paths. A flow rate of the coolant is adjusted by these adjustment pieces.
It is important to cool the rake surface when cooling the insert by using the coolant. The flow rate of the coolant is adjusted by these two adjustment pieces in the turning tool described in Patent Document 1. However, an operation to adjust the adjustment pieces is complicated. Adjustment positions of the adjustment pieces may be deviated due to, for example, vibration during the cutting process, resulting in insufficient cooling of the rake surface.
Patent Document 1: Japanese Unexamined Patent Publication No. 8-25111